True space exploration seems to be pretty much at a dead end these days. It's news when NASA pulls off a successful mission, and nobody talks much about sending humans to Mars anymore. Nobody, perhaps, except Carl Sagan, who has always been an evangelist for space exploration. Pale Blue Dot is his latest pulpit-pounder on the topic—and despite the climate of the times, it's downright inspirational. The Dot in question is Earth, and Sagan argues eloquently that we'll eventually leave this bit of rock to put down roots on other worlds.
It will be hard, admits the astronomer, but when he takes us through the process of setting up shop on Mars, the asteroids and beyond, it all sounds so reasonable. Sagan also recognizes that politicians won't easily cough up the billions and billions of dollars required for such schemes. But taken together, all of the arguments in favor of space travel—technological spinoffs, access to mineral riches, boosting science education, promoting international cooperation—might just tip the balance.
The truth is that they probably won't for the foreseeable future. It doesn't matter, though. It's wonderful fun to listen to Sagan pull out all the stops and to see the fanciful illustrations of how it all might happen. There are plenty of spectacular photographs of the planets and stars as well, and even a shot of the comet smashing into Jupiter last summer. Pale Blue Dot is one sermon that's worth sitting through. (Random House, $35)